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NFourierSeries

NFourierSeries[expr, t, n]
gives a numerical approximation to the order n Fourier exponential series expansion of expr, where expr is a periodic function of t with period 2 pi.
  • The numerical approximation to the order n Fourier exponential series expansion of expr is by default defined to be FkExponentialEImaginaryI k t, where Fk is given by .
  • Different choices for the period of expr can be specified using the option FourierParameters.
  • With the setting FourierParameters->{a, b}, expr is assumed to have a period of , and the order n Fourier exponential series expansion computed by NFourierSeries is , where Fk is given by .
Needs["FourierSeries`"]
Numerical approximation for an exponential Fourier series:
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Compare with a plot of the original periodic function:
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